WiFi Speed Issues?

[ckhooked]

Hi All,
I know this is an old thread, but it's right on the money regarding an issue I have.
I have a Samsung Galaxy S6 and an LG G Pad F 8.0.
My link speed on the Tablet is 150 Mbps and it's 585 on the S6.
I just got this tablet as a warranty replacement last week. It's refurb, and it's running Android 5. Samsung is running Android 6.
I don't know what the link speed was on my old tablet. But is there a setting on LG tablets where you can define the link speed?
I can't get back to the topic now, but there was a guy that said 'Duh, I forgot to turn off my Cell Data' He said his devices were much closer after that.
Was he talking about turning off Mobile Data? Surely not...

Any ideas out there?

Thanks